Internal-combustion engine



H. A. BULLARD INTERNAL COMBUSTION ENGINE Feb. 22 1927.

Filed Aug. 2, 1919 3 Sheets-Sheet 1 A W 61. (Laws INVENTOR m A TTORNEY Febo 1927" H. A. BULLARD AL COMBUSTION ENGINE INTERN Filed Aug. 2, 1919 v 3 Sheets-Sheet 2 Mk A 98 INVENTOH 1,618,806 Feb. 22,1927. HA. BULLARD INTERNAL COMBUSTION ENGINE Filed Aug. 2, 1919 3 Sheets-Sheet 5- m MM INVENTOR A HORNE Y Patented Feb. 22, 1927. UNlTED STATES PATENT @FFl-QE.

-HERBEB'1 A. BULLABD, OF NEW YORK, N. Y., ASSIGNOR TO MULTI VANE CONSTRUC- TION COMPANY, INC., 501 NEW YORK, N. I, A CORPORATION 01? YORK.

m'rnnnnn oomusrron ENGINE.

Application filled August a, 1919.- Serial No. 314,882.

My present invention relates to an inter-v exhausted from the explosionchamber after nal combustion engine, of rotary type, in being expanded therein to substantially atwhich a liquid or gaseous fuel is first commospheric pressure, I pressed and thenfired and exploded to do As another feature, I provide a tank filled 5 its work without the use of reciprocating with air or other inert gassunder pressure 60 parts; and the object of the invention is to which is so connected t rough a suitable providea rotaryengine which, by the elimi valve with the engine and with the fuel and nation of many of the troublesome parts and oil supply that, under the. control of this accessories essential to the engines of this single valve, the engine can vbe started in class now in commercial use, is simple in either direction and issupplied both with 65 its construction and operation and which fuel and oil under pressure of gas from the by reason of its high efliciency permits of tank which is kept filled at a pressure autoa considerable reduction in weight per horse matically restored and maintained by the power developed. operation of" the engine, thus providing a With this end in view, my new rotary self-starting reversible engine which is op- 70 engine comprises,.as one of its features, two erated entirely .without the use of extranerotors which are'mounted eccentrically One ous pumps. a, within the ,other and operatively connected 7 A third feature consists in a novel air to rotate together and a plurality of radially cooling and scavenging system by which air disposed vanes hich are mounted in the drawn in through the heads of the casing, 7

rims of the 1 rotors by hinge joints per-v to the center of the inner rotor is forced mittin a.-sliding movement ofithe vanes outwardly through the hollow van in throng the rim of one or both of the rotors theclosed space between the outer'frotor and and which subdivide the enclosedcrescentthev casing whereit is further compressed shaped space formed between the rotors into by the vanes and utilized scavenge the Q a series of contracting and expanding e'xexplosion chambers successively'jjatzthe point; plosion chambers. These rotary parts may of exhaust. g f j be conveniently mounted in a cylindrical Still another feature isiprovidedby aconcasing, the inner. rotor preferably concentric TQ tiO-II which at the iprope'r'moment in so ith andthe outer rotor consequently their revolution allows a ila-sl1--t iackcit-thewcentric to the casing, which thus forms befuel charge exploded in 'one chamber into tween its walls and the outer rotor an enthe next Succeeding-chamber to ignite the closed crescent-shaped, space 0 positely discharge th i s r quiring e s f a posed to that formed between t e tworotors, spark plug, one which can be operated by a,

tend, and which provides in its headt suit-, a o y for Starting e ng able inlet aridjexhaust ports .for' the ex 10. The invention also embraces the othersion chambers. I thus obtain a wellal-- novel features of form, arrangement, and anced engine, and auxiliary fan, in which combination of parts hereinafterdescribed is almost entirely eliminated and which, pended claims. 1

with running clearances of from three to The invention. will be understood by ref five thousandths of an inch, is free running, ere-nee to [the accompanying drawings lends itself to eas and complete lubrication, wherein is shown by wayof illustration,

a minimum since such leakage as takes p ace features-mention andin whichis from one to an adjoining chamber where Figure 1 is a view of the engine in front it still does useful work;and by spraying elevation, with'parts-broken away to showthe, fuel into the explosion chambers through the inter or artly in elevation and partly a into which the outer ends of the vanes exdry battery or bya plain magneto without sliding frictional contact between the parts vandimore particularly pointed out in the apd and'reduces loss y' leakage back or sli to an engine embogying all of the different 100.

50 a needle valve or other suitable injector at in' section; ig. 2 a section on the broken a'point in their revolution where they are line 22 of Fig.- 1; Figs. 3, 4, and 5, secfilled with air under little more than atmostional' detailstof the control valve on the pheric pressure I am able to dispense with lines; 3. 3, 4 4, and 5 5 of Fig. 2', respecthe usual carburetor, while no mufller is re,- .tively, showing the valve closed; Fig, 6' 55 quired since theproducts of combustion are 'a broken detail, in longitudinal section, of- 1 the needle valve employed as an in'ector at each of the four fuel inlet orts; ig. 7, a rspective view of one of tie vanes, partly roken away, and of one of its two wedgeshaped packings; and Fig. 8, a diagrammatic view of the pressure, fuel, and oil tanks and of their connection with each other and with the engine, shown in perspective from the back, showing the connections through the control valve as they are when the valve is turned to open position to start and run the en ine in viewe -froin the front of the engine.

The same reference characters indicate like parts throughout the several figures.

Referring to the drawings, the engine casing, which is to be supported in any suitable manner, consists of an annular rim 1 and front and rear head plates 2 and 3. The rim is hollow and the annular chamber 4 is formed therein, provided as here shown with lower water inlet 5 and upper water outlet 6, serves as a water jacket, although it may be used, if found desirable, as the pressure storage tank to which reference is hereinafter made; and each of the two head plates bolted or otherwise secured to the rim, is offset centrally to form an inwardly projecting sleeve or hub which provides a central air inlet 7 and an inner bearing 8, preferably concentric or substantially concentric with the casing, and an outer bearing 9 eccentric both to the inner bearing and to the casin The casing also has, formed in each, head, an inwardly open ignition chamber or recess 10, above the hub, into the wall of which is set a spark plug 11, and, below the hub, a chamber 12 which in the front head is an air-chamber and is provided with horizontally elongated inlet 13 and outlet 14 and in the rear head is an exhaust chamber having a horizontally elongated inlet 15 and circular threaded outlet 16 for an exhaust pipe. The casin is further provided, front and rear, with eft pressure inlet ports 17 and 18 andright pressure inlet ports 19 and 20, with right fuel inlet ports 21 and 22 and left fuel inlet ports 23 and 24, and lubricant inlet ports 25 and 26; and each of the four fuel inlet portsis equipped with an injector or spraying device which, as shown, is an ordinary needle valve comprising a hollow plug 27, with contracted orifice 28 controlled by an adjustable needle 29, and is screwed into the inlet port.

The inner rotor of the engine, made up of a ring 30, with inte ral flanges 31 projecting inwardly therefiom on either side, and of two annular. plates 32 and 33, both alike, which are set into annular recesses in the outer faces of the flanges and are there secured in place by screws or otherwise and are oflset inwardly-to provide hubs 34, is mounted to rotate, on suitable roller or other bearings 35, upon the inner hub a counter cloclewise direction,

bearings 8 of the casing. It has, around its periphery, a series of transverse cylindrical sockets 36, which separate the ring proper betweemthe two flanges into sections and provide seats for the bin e joints of the vanes, and, both front and rear, an intermediate series of radial round-bottomed grooves 37 which are inclined so as to form prongs from the sides to the periphery of the rotor and serve a purpose to be hereinafter described. It is packed, around'the central openings 38 in its ends which register with the air inlet openings in the heads of the casing, by packing rings 39 which are spring-mounted ingrooves 40 provided for the purpose in the ends of the casing hubs and the front and rear plates.

This rotor is connected with the main engine shaft 41 journ aled in a suitable thrust bearing 42 mounted on a bracket 43 on the back of the casing, by means of rods 44 which for convenience of manufacture are riveted at one end in openings 45alternately in one end and in the other of the two plates and at the other end fit into sockets 46 in the opposite plate and which pass through openings 47 provided therefor in a flange 48 on the end of the shaft, the flange sliding freely upon the rods so as to take up any end thrust on the shaft without transmitting it to the engine. A magneto drive shaft 49 is shown as keyed to the main shaft by oppositely projecting lugs 50 on its reuccd end which fits into a correspondingly shaped socket 51 in the endof the shaft.

Th outer rotor consists of a series of ring bear against the outer surface of sections 52 which. are lon itudinally grooved at 53 to increase their rac iating surface and form, between EtClJOlIllIlg sections, a series of transverse cylindrical sockets 54 correspond mg in number and angular position to the.

similar sockets in the periphery of the inner rotor, and of two like annular plates 55 and 56 which are secured to the ring sections by screws and hold them in place and are offset outwardly around their vide. hubs 57 by which this rotor is mounted, with roller bearings 58 separated by washers 59 from the similar bearings of the inner rotor, upon the outer bearings 9 on the casing hubs. Each plate has intersecting radial and circumferential oil grooves 60 and 61 in its outer surface and a circular series of round openings 62 alternating with similar but smaller openings 63 which, front and rear, register with the ignition ch'ambers, the pressure, fuel, and lubricant inlet ports, and the outlet from the air chamber and the inlet to the. exhaust chamber in the heads of the casing. V

The two rotors are operatively connected, so as to rotate synchronouslv about their eccentric axes, by means of skeleton split disks 64 which turn within the larger openings'62 inner edges toproplug, and these grooves,

inthe sides of the outerrotor and upon the ends of studs passing through holes 66 extending across the rim of the inner rotor, the kidney-shaped openings 67 in the disks providing passages of substantially the same area as those provided by the smaller openings 63; and the crescent-shaped chamber formed between the rims of the rotors is divided into a series of explosion chambers 68 by vanes 69, made for convenience in two sections, which, channeled to provide a narrow air-passage 70 (interrupted by supports 71) extending from inner to outer end an having wedge-shaped packing pieces 72 mounted by tongue and to slide upon inwardly tapered, edges, are hinged at their inner ends to the inner rotor, by two segmental strips of this rotor and grooved on their inner faces to accommodate locking shoulders 74 on the vanes, and slide between plain segmental strips 75 fitted with packings 76 and rocking in the sockets of the outer rotor.

The control valve, which is shown as mounted upon the top of the engine easing.

but may be located whereverfound convenient, consists of a double plug 77 and of two thimbles 78 and 79, provided with pedestals by which they are mounted on the casing, within the tapered walls of which, the tapered ends'of the plug, adjustably secured front and rear by bolts 80 and 81set into the ends of the plug and provided withadjusting nuts 82 and 83, are rocked by a valve lever 84 secured to the plug between the two thimbles. For a .double control of the pressure system of the engine, the valve plug has, both front and rear, two transverse grooves and connecting passage 85, 86, 87 and 88, 89, 90, which are connected together by a longitudinal passage 91 and which co-operate with an inlet port 92 and three outlet ports 93, 94, and 95 in the front thimble and with similar inlet and outlet port's 96, 97, 98, and 99 in the rear thimble. The fuel system is controlled through transverse grooves 100 and 101 in the frontand rear portions of the connected together y a longitudinal passage 102, co-operate respectively with an inlet port 103 and two out-let ports 104 and 105 in the front thimble and with twooutlet ports 106 and 107 in the rear thimble. And the lubricating system is similarly controlled through front and rear circumferential grooves 108 and 109 in the plug, with connecting longtiudinal passage 110, respectively co-opera'ting with'an elbow outlet port 111 in the front thimble and an inlet port 112 and elbow outlet port 113 in the rear thimble.

For the operation of the engine there are provided a pressure storage tank 114, a fuel. tank 115, and a lubricant tank 116/ The.

pressure storage tank is connected by pipe 117 and branch pipes 118 and 119 to the'two outlet port 93,

groove connections 7 3 fitting the sockets. from the valve outlet the control lever to and the fuel illustrated inlet ports 92 and 96 of the control valve and through the valve to the top of the fuel tank by pipe 120 leading from the valve with the top of the lubricant tank by pipe 121 leading from the valve outlet port 97, and with both the front and the back of the engine either by pipes 122' and 123 from the valve outlet ports 94 and 98 to the left pressure inlet ports 17 and 18 or by pipes 124 and 125 from the valve outlet ports 95 and 99 to the right pressure inlet ports 19 and 20. The fuel tank, connected with the pressure storage tank as described, is connected to the control valve by pipe 126 leading to the valve inlet port 103 and through the valve either with the right side of the engine by pipes-127 and 128 ports 104 and .106 to the injectors in the front and rear fuel inlet ports 21 and 22 or with the left side of the engine by pipes 129 and 130 from the valve outlet ports 105 and 107 to the injectors in the front and rear fuel inlet ports 23 and 24. The lubricant tank is connected, in ad-- valve and through it with both the front and the back 'ofthe engine by pipe 131 to the valve inlet. port 112 and by pipes 132 and 133 from the vvalve outlet ports 111 and 113 to the two lubricant inlet ports 25 and 26.

With the control lever in central vertical position, the valve is closed and all the connections of the pressure, fuel, and lubricant tanks With each other andfwith the engine are cut off (see Figs. 2-5). Upon turning the left .(as viewed from the front of the engine), the pressure tank is connected with the fuel and lubricant tanks and the three tanks are-connected with the engine, the pressure tank with its left tank with its right side (also as viewed from the front) Or by turning the control lever to the right, the connections of the pressure. and fuel tanks with the engine will be reversed, that is to say, will be made with the right and the left side of the engine respectively, while the connections of the pressure tank with the fuel andlubricant tanks and of the latter with the engine will be as before, and

the engine will run in a clockwise direction.

The operationof the engine, which is the same in whichever direction it is thus started,

where the control lever has been turned to the left and the valve plug is in the position in Fig. 8: The air or other inert gas in the pressure tank is forced to the f-ront and rear pressure inlet ports in the left side of the engine a front and rear opening ing 62 as the case may and theneethrough 63 (or disk in openbe) in the sides of the outer rotor and radial grooveBZ in the I and the engine'will start to run meounter-clockwise d rection.

balance with the sides and peri hery of the inner rotor into both ends of the explosition chamber which happens .to be in register therewith and which at this point in its cycle has a relatively small area. Thepressure of this air upon the walls of the ex losion chamber, acting u on the larger su ace of the lower vane an upon the rims of the rotors, starts the engine counter-clockwise; whereupon, as the engine begins to turn, this explosion chamber passesout of, and the next and succeeding chambers pass into, register with the pressure inlet ports, and the pressure of the air thus admitted tothese chambers acts in the same way as in the first and accelerates the engine. Meanwhile the from the fuel tank, under pressure fromad pressure tank, has been sprayed by the injectors in the front and rear fuel inlet ports on the right side of the engine through openings 63 (or disks in o enlngs 62) into the ends of first one an then another explosion chamber at 'a point in its cycle where the area of the chamber is close to maximum, and, as each chamber in turn passes out of register with these fuel inlet ports the explosive mixture confined therein is compressed by the drawing together of the rims of the two rotors until, at the,top of the engine where compression is maximum, the compressed charge is brought into communication with the ignition chambers, through the openings and grooves, and is exploded; and, as the first fuel charge is fired, the i ition chambers which are made wider t an that part of the plates of the outer rotor between an opening 63 and-the opening in the adjacent disk, permit a flashback into the next explosion chamber, thus rendering the further use of the spark plugs unnecessary for the continued operation of the engine. Moreover, after the firing of the fuel charges has begun therunning of the engine is effected, as usual, bythe expansion of the fuel charge first compressed and then fired in the successive explosion chambers, while the pressure in the ressure storage tank is restored to and maintained on a ressure of the expanding products of com ustion in the explosion chambers at the int in their cycle where they come in register with the pressure inlet ports. The products of combustion are exhausted from the explosion chambers, after expanding therein to substantially atmospheric pressure, and the chambers are both cooled and scavenged. by air which, throughout the o ration of the engine, is drawnin from t e outside to the interior of theinner rotor through the central air inlets 7 in the heads of the casingand is thence forced outwardly through the passages in the vanes into the crescent-shaped space formed between the rim of the outer rotor and the casing where it is further compressed or forced onward by the projecting outer ends of the vanes and is forced under compression to the bottom of the engine 16, leaving each ex losion chamber after pamin the exhaust lled with fresh heated air. urthermore durin the entire operation of the engine, oil fi tank is forced under pressure from the pressure tank through the front and rear inlet ports into the races of the roller-bearings "of the rotors and thence into the radial and circumferential grooves in the plates of the outer rotor, where it forms an oil packing, and between the plates of the inner and outer rotors and into the bearings of the vanes, thus keeping the engine thoroughly lubricated without the use of'the usual extraneous oil pump.

Havingexplained the principle of my in-- vention and illustrated and described what I now consider to be the best form of engine om the lubricant,

in which to embody that principle, what I 7 claim as new, and desire to secure broadly by Letters Patent, is-

1. An internal combustion engine comprising two rotors mounted to rotate together one within and eccentric to the other by means of disks turning in bearings in the sides of the outer rotor upon studs set in the rim of the inner rotor and radial vanes hinged in the rim of one and sliding in bearings in the rim ofthe other rotor, forming a series of expanding and contracting chamers.

2. An internal combustion engine com'prising two rotors mounted to rotate together one within and eccentric to the other and a series of radial vanes hinged in the rim of one and sliding in bearings in the rim of the other rotor, forming a series of expanding and contracting chambers, means for supplying fuel to said chambers successivelyat a polnt to one side of a plane through the axes of the two rotors, means for firing the fuel charge within the chambers at a point substantially in said plane adjacent the axis of the inner rotor, and means for exhausting the products of combustion fromthe chambers at a point substantially in said plane adjacent the axis of the outer rotor.

3. Ar; internal combustion engine comprising two rotors mounted to rotate together one within and eccentric to the other and radial vanes hinged in the rim of one and sliding in hearings in the rim of the other rotor, forming a series of expanding and contracting chambers, means for supplying fuel to the chambers at a point either on one or the other side of a plane passing through the axes of the two rotors, means for firing the charges within the chambers at a point substantially in said planeadjacent the axis of the inner rotor, and an exhaust outlet connecting with the chambers at a point substantially in said planeoadjacent the axis of the outer rotor.

4. An internal combustion engine comprising two rotors mounted to rotate together one within and eccentric to the other and radial vanes hinged in the rim of one and sliding in the rim of the other rotor, form? ing a series of expanding and contracting chambers, means for admitting fuel to the said chambers on one side of a plane passing through the axes of the two rotors, means for firing the fuel charges in the chambers at a point substantiall in said plane adjacent the'axis of the innen rotor, passages adapted to connect each chamber when at said firing point with the next succeeding chamber, and means for exhausting the chambers at a point substantially in said plane adjacent the axis of the outer rotor.

5. An internal combustion engine comprising two rotors mounted to rotate together one within and eccentric to the other and radial vanes hinged in the rim of one and sliding in bearings in the other rotor, forming a series'of expanding and contracting chambers, means for supplying fuel to the cha'mbersat'a point either on one or on the other side of a plane passing through the axes of the two rotors, means for firingthe fuel charge within the chambers at a point substantially in said plane adjacent the axes of the inner rotor, passages connecting each chamber when at saidfiring point with the next succeedin chamber on either side, and means for ex austing, the chambers at a point substantially in said plane adjacent the axis of the outer rotor.

6. An internal combustion engine comprising two rotors mounted to rotate together one within and eccentric to the other and radial vanes with passages extending from end to end hinged? in t e rim of one an sliding in hearings in the rim of the other rotor, forming a series of expanding and contracting chambers, and connections between a source of cooling medium and the inner ends of the passages through the vanes.

7 An internal combustion engine comprising two rotors mounted to rotate together one within and eccentricv to theother and radial vanes having passages extending from end to end and hinged in the rim of one and sliding in bearings inthe rim of the other rotor, forming a series of expanding an contracting chambers, an exhaust port with which each chamber isin communication at a. given point in its revolution, and connections connecting the inner ends ot the passages through the vanes with the air outside the rotors and the outer ends of the passages through the vanes with the exhaust through the chambers in succession.

8. An internal combustion engine comprising two rotors mounted to rotate together one within and eccentric to the other and radial vanes hinged in the rim of one and sliding in bearings in the rim of the other rotor, forming a series and, contracting chambers, means for supplying an inert gas under pressure to the chambers at a point on one side of a plane passing through the axes of the two rotors at whichthe area of the chambersis relatively small, means for supplying fuel to the chambers at a point on the opposite side of said plane at which the area of the chambers is relatively large, means for firing the fuel charges within the chambers at a point substantially in said plane where the area of the chambers is approximately minimum, and -means for exhausting'the products of combustion from p the chambers at a point substantially in said plane where the area of the chambers is approximately maximum.

9.' An internal combustion engine comprising two rotors gether one within and eccentric to' the other and radial vanes hinged in the .rim of one and sliding in hearings in the rim of the other rotor, forming a series of expanding and contracting chambers, means for supplying compressed air point either on one side or the other of a plane passing through the axes of the two rotors where th'e area of the chambers is relatively small, means for supplying fuel underpressure of the compressed air to the chambers at a point on the 'sideof said plane opposite that side on which the compressed air is supplied where the area of the chambers is relatively large, means for firing the fuel charges within the chambers. at a point substantially in cent the axis of the inner rotor, and means for exhausting the products of combustion from the chambers at a point substantially d in said plane adjacent the axis of the outer of the two rotors where the area of the chambers is relatively small, means for suppl ing fuel under pressure of the compresse tothe chambers both from the back and from the front of the engineon the side of the plane opposite 1 that side on which the said plane ad aof expanding mounted to 'rotatetoto the chambers at a com ressed air is sup lied where -the area of t e chambers is'relhtively large, means for firing the fuel charges-within the chamat apoint substantially in said plane adjacent the axis of the inner rotor, and means for exhausting the products of combustionfrom the chambers at a oint substantially .in said plane adjacent t ea'xis of chambers which the inner ends of the outer rotor.

11. An internal combustion engine comprising a casin two rotors mounted therein to rotate toget er one within the other the inner rotorj about an axis substantially concentric with the casin and the outer rotor about an axis eccentric both to the inner rotor and to the casing and radial vanes rovided'with assages extending from en to end hinged in the rim of wound sliding in bearings in the rim of the other rotor, forming a series of expanding and contracting chambers, means for supplying air to the at a point either on one side or the other of a plane passing through the axes of the two rotors where the area of the chambers is relatively small, means for supplying fuel under pressure of the compressed air to the chambers at a point on the side of said plane opposite that side on the compressed air is supplied where the area of the chambers is relatively lar means for firing the fuel charges within t e chambers at a int,,substantially in said plane adjacent a: of the. inner rotor, means for exhausting the products of combustion from thechambers at a point substantially in said plane adjacent the axis of the outer rotor, and means for connecting the passages in the vanes with the air outside the en inc and the outer ends of said passages wit the chambers at the oint of exhaust.

1 The combination in a rotary gas engine comprising a series of expanding and contracting chambers separated by radial walls of a cooling ystem comprisin as elements thereof a extending hrou h said walls from the inner to thejouter en thereof.

13. The combination in a rotary gas engine of a casin to rotate toget er one within and eccentric to the othen-anda series of vanes hinged in one and sliding through packing bearings in the other rotor and having longitudinal passages connecting at one of their two ends with a cooling me ium and at'the other end with the interior of the casing outside the outer rotor.

14. The combination in gine of a casing, two rotors mounted therein to rotate to ether one within the other and one approximately concentric with and the other eccentric to the casin and a series of radially dis osed vanes hinged to one and sliding in wings in the other rotor a rotary gas enchamber.

, two rotors mounted therein and hair 10 'tudinal passages connected at their fiel'zi ds with the air outside the casing and at their outer ends with the exhaust of the engine through the chambers, formed by the vanes between the rims of the two rotors.

15. The combination in a rotary gas engine comprising a series ofexpanding and contracting chambers of means for supplying compressed air to the successive chambers at a point on one side of the en inc to start the engine, means for supplying uel under pressure of the compresse successive chambers at a point on the oppo site side of the engine, means for firingthe fuel charge enclosed within the chambers at a point in the cycle where their area is substantially at a minimum, and means for producing a back firing from the'fuel "charge fired at such point into the'next succeeding 16, The combination in a rotary gas engine comprisinga series of expanding and contracting chambers of means fonsu plying an inert gas under pressure to the c ambets on one side of the engine at a point in the cycle where their area is close to a minimum, and means both for 'supplying fuel to the chambers on the opposite sidejof the engine at a pointin the cycle where their areais close to a maximum and for firing the fuel charge in saidchambers at a point where their'area is substantially at a minimum..

17. The-combination in a rotary gas engine comprising a series of expanding and air to the I contracting chambers ofmeans for supply ing an inert gas under ressure to the c ambers on either side of t 0 engine at a point in the cycle where their area is close to a maximum means for suppl ing fuel under pressure from said gas to chambers on the side of the engine opposite that to which said gas is supplied at a point in the cycle where their area is close to a maximum, and means for firing the fuel injsaid chambers at a point in the cycle where their area is substantially at a minimum.

18. The combination in a rotarygas engine comprising a series of expanding and contract ng chambers of means for supplying an inert gas under pressure to the ens gine; means for supplying fuel to the engine under ressurefrom said inert gas, and means or utilizing the expanded products of combustion in the engine to maintain the pressure of said inert gas.

19. The combination in a rotary gas engine comprising a series'of expanding and contracting chambers of means for supplying an inert gas under pressure to the engine, means for said inert gas, restoring and maintaining the pressure, of

at which the gasis supplied thereto.

= firing. the fuel charge in the chambers sucminimum and from combination with a series of rotary expandsaid inert gas during the operation of the: engine. of the engine.

20. The combination in a rotary gasv en- 25. The combination in a rotary gas gine comprising a series of expanding and engine comprising a series.of expanding and contracting chambers of means for supplycontracting chambers and suitable firing and ing an inert gas under pressure to the engine exhaust means of a pressure tank adapted to start the same, means for supplying both lubricant and fuel to the engine under presand between the fuel tank and the other side compression, sure from said inert gas; and means for trolled connections from the pressure tank maintaining the pressure of said inert gas both to the fuel tank and to the successiveat a parity with the pressure of the expandchambers at a point on one side of the engine ing products of fuel combustion in the chainand from the fuel tank to the successive hers at a point in the cycle of the engine chambers at a point on the opposite side of the en ine.

21. In an internal combustion engine, the k 26. combination with a series of rotary expandengine comprising a series of expanding and ing and contracting chambers of a source of contracting chambers 0t a pressure tank supply of acompressed inert gas connected adapted to Contain a pply. f, 1 ui l with the chambers successively at a point gas under compressioma fuel tank, connecin the cycle where the area of each is near i ns from he pressure tank both to the fuel the minimum and of a source of fuel supply tank and to the successive chambers at points connected with the chambers successively 100th Sides of he eng ne and from the at a point in the cycle where the area of each l v -1 t0 u cessive chambers at is near the maximum and of means for points on bothsides of the engine, and control means adapted to open the connections cessivelyat a pointin the cycle'where the m th Pr Ie tank to the fuel tank and area of eachuis at substantially the minimum. t the ha rs on either one of the 1 two 22. In an internal combustion engine,

combination with a series of rotary expand- 'to the chambers on the opposite side-of the ing and contracting chambers of a ressure engine.v tank, a fueltank, and connections mm the 27. The com at rotary gas pressure tank both to the fuel t k a d t engine comprising a series of expanding and the chambers successively at a point in the n r ing hamb rs of a cycle where the area of each is close to a adapt d to contain asupply 0 the fuel tank to the under compression, chambers successively at a point in the cycle from the pres re tank b th o the fuel tank where the area of each is close to a maximum. and to the successive chambers at points on 23. In aninternal combustion engine, the

suitable gas ing and contracting chambers of a pressure tank, a fuel tank, connections from "the pressure tank both to the'fuel tank and tothe chambers on opposite sides of the engine at I one tank and the champoints in the cycle where the area is close bers on one side and between the other tank to a minimum'and from the fuel tank also and the chambers onthe opposite side of the to chambers on both sides of the en 'neat engine] a point in the cycl 1 where their area is close The cornbmation in to a maximum, add means forcontrolling engine compr sing ase said connections tostart and run the engine contracting chambers in either direction. adapted to contain a sup 24. In an internal combustion engine, the gas under compression, a

on both sides of the-engine, and asingle control valve adaptedto simultaneously open a rotary gas of a pressure 'tank 1y of a suitable el tank, a lubrito contain a supply of a suitable gas undera fuel tank, and suitably conressure tank th sides of the engine and from. the fuel tank a fuel tank, connections j both sides of the engine andfrom the fueltank to the successive chambers at points heconnection between the two tanks and the 1 ms of expanding and combination with a series of rotary -expand cant tank, connections from the pressure ing and contracting chambers, of a ressure tank to both, fuel and lubricant tanks and tank, afuel tank, and connections f i om the to the chambers at points'on both sides of pressure tank to the fuel tank and to the the eng ne and from chambers on opposite sides of the engine at the engme and from the fuel tank to the points in the cycle where their area to a minimum and from the fuel chambers on opposite sides of the en tank to engine, and .controlmeans for opening said ine at connections from the pressure tank to the points in the cycle where their area is close fuel and lubricant tanks and from the presto a maximum, said comiections being sure tank to the chambers ,on either one through a control valve adapted to simulof the two sides of the engine and from the taneously open the pressure tank-- and either side of the engine sides of the engine.

the lubricant tank to connection between the fuel tank. to the chambers on the opposite I 10 to the front and rear of the engine and from the fuel tank to the front and rear of the chambers at points on both sides ofthe engine, and control means for opening said connections from the pressure tank to the fuel and lubricant tanks and from the pressure tank to the chambers on either one of the two sides of the engine and from the fuel tank to the chambers on the opposite side of the en ine.

ERBERT A. BULLARD. 

